Risperidone Versus Olanzapine for Treatment of Schizophrenia

Abstract

We found no difference for the outcome of unchanged or worse in the short term (n = 548, 2 randomized control trial (RCTs), RR = 1.00, 95% CI = 0.88 to 1.15). One study favored olanzapine for the outcome of relapse/rehospitalization by 12 months (n = 279, 1 RCT, RR = 2.16, 95% CI = 1.31 to 3.54, NNH = 7, 95% CI = 3 to 25). Most mental state data showed the 2 drugs to be as effective as each other (n = 552, 2 RCTs, RR ‘no <20% decrease Positive and Negative Syndrome Scale by 8 weeks’ 1.00, 95% CI = 0.87 to 1.15) (Figure 1). Both drugs commonly cause adverse events: 75%given eitherdrug experiencedan adverse event; 20% experienced anticholinergic symptoms; both groups experienced insomnia although it was more frequent with risperidone (n = 1588, 5 RCTs, RR = 1.41, 95% CI = 1.15 to 1.72, NNH = 15, 95% CI = 9 to 41); and about 30% experienced sleepiness (n = 1713, 6 RCTs, RR = 0.92, 95% CI = 0.79 to 1.07). People given either drugoften experienced extrapyramidal symptoms (n = 893, 3RCTs,RR = 1.18, 95%CI = 0.75 to 1.88); 25% of people using risperidone and 18% of people using olanzapine required medication to alleviate these symptoms (n = 419, 2 RCTs, RR = 1.76, 95% CI = 1.25 to 2.48, NNH = 8, 95% CI = 4 to 25). People allocated to risperidone (13%) were less likely to gain more than 7% of their baseline weight compared with those given olanzapine (28%), and the weight gain was often considerable and of quick onset (n = 984, 2 RCTs, RR gain more than 7% of their baseline weight in the short term 0.47 95% CI = 0.36 to 0.61, NNH = 7, 95% CI = 6 to 10). Risperidone participants were less likely to leave the study due to metabolic side effects and weight gain compared with olanzapine participants (n = 667, 1 RCT, RR = 0.19, 95% CI = 0.08 to 0.45). Patients on risperidone were more likely to experience abnormal ejaculation (n = 370, 2 RCTs, RR = 4.36, 95% CI = 1.38 to 13.76, NNH = 20, 95% CI = 6 to 176). Both drugs are associated with high attrition rates; in the long term, 66% of those allocated risperidone left the study early compared with 56% given olanzapine (n = 1440, 5 To whom correspondence should be addressed; tel: þ44-1133058302, fax: þ44-113-277-2830, e-mail: [e-mail]. Schizophrenia Bulletin vol. 33 no. 6 pp. 1274–1276, 2007 doi:10.1093/schbul/sbm101 Advance Access publication on October 5, 2007